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Model 400E Ozone Analyzer
Instruction Manual
THEORY OF OPERATION
P/N 04316 Rev: B
237
10.4.
Interface
The analyzer has several ways to communicate the outside world, see Figure 10-6.
Users can input data and receive information directly via the Front Panel keypad
and display. Direct communication with the CPU is also available by way of the
analyzers RS232 & RS485 I/O ports. The analyzer can also send and receive
different kinds of information via its External Digital I/O connectors and the three
Analog Outputs located on the Rear Panel.
Mother
Board
Status Outputs:
1 – 8
Control Inputs:
1 – 6
CPU
RS–232 ONLY
RS-232 or RS–485
KEYBOARD
RELAY
BOARD
PC/104 BUS
DISPLAY
I
2
C BUS
I
2
C BUS
Analog Outputs
A1
A2
A3
Optional
4-20 mA
COMM B
Female
A4
COMM A
Male
Figure 10-8: Interface Block Diagram